@mixin flex-row {
  display: flex;
  flex-direction: row;
}
.index-list {
  height: 100vh;
  .nav-letter {
    position: fixed;
    right: 0;
    top: 0;
    bottom: 0;
    z-index: 99;
  }
  .nav-letter--wrap {
    display: flex;
    flex-direction: column;
    justify-content: center;
    height: 100vh;
  }
  .nav-letter--name {
    color: #666;
    width: 50px;
    text-align: center;
    margin-bottom: 5px;
  }
  .letter {
    padding: 10px 20px;
    color: #7f7f7f;
    font-size: 28px;
    background-color: #f7f7f7;
  }
  .area-name {
    padding: 20px;
    box-sizing: border-box;
    color: #333;
    font-size: 28px;
    -webkit-transition: background-color 0.3s;
    transition: background-color 0.3s;
    position: relative;
    border-bottom: 1px solid #f1f1f1;
  }
}
.platform-top {
  font-size: 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 30px;
  height: 80px;
}
.platform-blue {
  color: #12b3ff;
}
.platform-tips {
  font-size: 28px;
  padding: 0 30px;
  line-height: 60px;
  padding-bottom: 20px;
}
